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High-security nanoplatform with enhanced therapy compliance is extremely promising for tumor. Herein, using a simple and high-efficient self-assembly method, a novel active-targeting nanocluster probe, namely, Ag 2 S/chlorin e6 (Ce6)/DOX@DSPE-mPEG 2000 -folate (ACD-FA) is synthesized. Experiments indicate that ACD-FA is capable of specifically labeling tumor and guiding targeting ablation of the tumor via precise positioning from fluorescence and photoacoustic imaging. Importantly, the probe is endowed with a photodynamic "on-off " effect, that is, Ag 2 S could effectively quench the fluorescence of chlorin e6 (89.5%) and inhibit release of 1 O 2 (92.7%), which is conducive to avoid unwanted phototoxicity during transhipment in the body, and only after nanocluster endocytosed by tumor cells could release Ce6 to produce 1 O 2 . Moreover, ACD-FA also achieves excellent acid-responsive drug release, and exhibits eminent chemo-photothermal and photodynamic effects upon laser irradiation. Compared with single or two treatment combining modalities, ACD-FA could provide the best cancer therapeutic effect with a relatively low dose, because it made the most of combined effect from chemo-photothermal and controlled photodynamic therapy, and significantly improves the drug compliance. Besides, the active-targeting nanocluster notably reduces nonspecific toxicity of both doxorubicin and chlorin e6. Together, this study demonstrates the potency of a newly designed nanocluster for nonradioactive concomitant therapy with precise tumortargeting capability.

A graphene quantum dot (GQD) is a novel carbon nanomaterial with the advantages of low cost and no pollution. It has attracted serious attention in the biomedical fields because of its stabilities and tunable fluorescence wavelength. In this manuscript, an N-doped graphene quantum dot (N-GQD) was synthesized by a hydrothermal method using citric acid as the carbon source and urea as the nitrogen source. X-ray diffraction, Raman spectroscopy, transmission electron microscopy, UV-vis absorption spectrum, and fluorescence spectrum were used to characterize the N-GQD. The results showed that the N-GQD had a uniform size of about 5 nm. The two fluorescence emission peaks, one in the visible light region showed a 49.75% quantum yield, while another in the near infrared region was 2.49%. The photothermal conversion efficiency was 62.53%, higher than any kind of carbon nanomaterial in existence today. MTT and a long-term cytotoxicity experiment confirmed that the N-GQD had low cytotoxicity. The probe also had the ability of photoacoustic response at the same time. After coupling with folic acid, it presented imaging and photothermal therapy on the cells, which has great application prospects in the early diagnosis and treatment of tumors.

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Ameliorated therapy based on the tumor microenvironment is becoming increasingly popular, yet only a few methods have achieved wide recognition. Herein, targeting multifunctional hydrophilic nanomicelles, AgBiS 2 @DSPE-PEG 2000 -FA (ABS-FA), were obtained and employed for tumor treatment. In a cascade amplification mode, ABS-FA exhibited favorable properties of actively enhancing computed tomography/infrared (CT/IR) imaging and gently relieving ambient oxygen concentration by cooperative photothermal and sonodynamic therapy. Compared with traditional Bi 2 S 3 nanoparticles, the CT imaging capability of the probe was augmented (43.21%), and the photothermal conversion efficiency was increased (33.1%). Furthermore, remarkable ultrasonic dynamic features of ABS-FA were observed, with increased generation of reactive oxygen species (24.3%) being obtained compared to Ce6, a commonly used sonosensitizer. Furthermore, ABS-FA exhibited obvious inhibitory effects on HeLa cell migration at 6 μg/mL, which to some extent, demonstrated its suppressive effect on tumor growth. A lower dose, laser and ultrasonic power, and shorter processing time endowed ABS-FA with excellent photothermal and sonodynamic effects. By mild cascade mode, the hypoxic condition of the tumor site was largely improved, and a suitable oxygen-rich environment was provided, thereby endowing ABS-FA with a superior synergistically enhanced treatment effect compared with the single-mode approach, which ultimately realized the purpose of "one injection, multiple treatment". Moreover, our data showed that ABS-FA was given with a biological safety profile while harnessing in vivo. Taken together, as a synergistically enhanced medical diagnosis and treatment method, the one-for-all nanoplatform will pave a new avenue for further clinical applications.

Multifunctional nanoprobes that can be applied for real‐time monitoring or precision treatment of tumors have received wide interest among researchers. However, most of these nanoprobes are obtained through chemical synthesis, and thereby may contain toxic residues or harmful reagents. In this article, a nano‐bismuth‐sphere‐cluster (Bi) is synthesized via a one‐step method (after an irradiation with ultra‐violet) and is then applied in dual‐mode computed tomography/photoacoustic imaging. Bismuth potassium citrate granules, which is a common gastric drug that is highly safe and has a low price (<1 China Yuan/g), is used as the only raw material. The results show that the Bi cluster has good stability with sizes of about 25–55 nm, and a photothermal conversion efficiency as high as 39.67%. After being adsorbed onto doxorubicin, the Bi cluster can be used directly in animal experiments. Due to the effect of enhanced permeability and retention, the probe can easily enter tumor cells. Drug release can be controlled by a near‐infrared laser and the acidic environment of tumor cells, which indicates that the combined chemo‐photothermal therapy is achieved. This work presents a new dual‐mode bio‐imaging and combined chemo‐photothermal therapeutic nanoprobe that can be applied in theragnostics for tumors.

Colorectal cancer is one of the malignant tumor with high morbidity and lethality. Its efficient diagnosis and treatment has important significance. In this study, the orthotopic cancer model mouse which...

Given their superior penetration depths, photosensitizers with longer absorption wavelengths present broader application prospects in photodynamic therapy (PDT). Herein, Ag2S quantum dots were discovered, for the first time, to be capable of killing tumor cells through the photodynamic route by near‐infrared light irradiation, which means relatively less excitation of the probe compared with traditional photosensitizers absorbing short wavelengths. On modification with polydopamine (PDA), PDA‐Ag2S was obtained, which showed outstanding capacity for inducing reactive oxygen species (increased by 1.69 times). With the addition of PDA, Ag2S had more opportunities to react with surrounding O2, which was demonstrated by typical triplet electron spin resonance (ESR) analysis. Furthermore, the PDT effects of Ag2S and PDA‐Ag2S achieved at longer wavelengths were almost identical to the effects produced at 660 nm, which was proved by studies in vitro. PDA‐Ag2S showed distinctly better therapeutic effects than Ag2S in experiments in vivo, which further validated the enhanced regulatory effect of PDA. Altogether, a new photosensitizer with longer absorption wavelength was developed by using the hitherto‐unexplored photodynamic function of Ag2S quantum dots, which extended and enhanced the regulatory effect originating from PDA.